C60on strain-relief patterns ofAg∕Pt(111): Film orientation governed by templat

Abstract

The adsorption, growth and overlayer formation of C 60 fullerene molecules on strain-relief patterns induced by 2 monolayers of Ag on Pt͑111͒ ͑Ag͑2ML͒/Pt͑111͒͒ is investigated by means of scanning tunneling microscopy. The Ag͑2ML͒/Pt͑111͒ template surface consists of periodic crossing dislocations separating face-centered cubic ͑fcc͒ and hexagonal close-packed ͑hcp͒ stacking domains. At room temperature, C 60 molecules are found to be sufficiently mobile on the template surface to cross the dislocations and to self-assemble into large hexagonally close-packed two-dimensional islands. The nucleation and growth of the C 60 islands takes place not only at the step-edges, but also in the middle of terraces. The islands cover as well fcc as hcp domains of the template, in a near commensurate fashion with respect to the Ag͑2ML͒/Pt͑111͒ superstructure. This commensurability manifests itself by a transfer of the strain relief superstructure into the molecular film via a "lock to register" mechanism. The Ag͑2ML͒/Pt͑111͒ superstructure acts on the molecular film by orientating the C 60 close-packed rows along the Ag͗110͘ direction. This is different from the usual orientation of a C 60 film on a standard and unreconstructed Ag͑111͒ substrate, namely it is rotated by 30°. The C 60 "lock to register" phenomenon can find interpretation in a strong substrate-molecule interaction, which can result in a significant compression of the C 60 lattice. Here, a special role is played by Ag͑2ML͒/Pt͑111͒ small hcp stacking domains enclosed by strong discommensuration lines, foremost responsible for the "lock to register" mechanism.

Stepwise self-assembly of C60 mediated by atomic scale moiré magnifiers

“…It could be exploited as a new type of substrate-assisted particle self-assembly for the construction and size selection of large molecular devices. Such a new approach to the substrate-assisted self-assembly of size-selected structures via 'moiré shell closure' is conceptually very different from the previous approach that uses surfaces with large superstructures of quasi-periodic inhomogeneous adsorption sites [2][3][4][5][6][7] as 'anchor sites' to assist the aggregation of particles and achieves size selection. The creation of an ensemble of monodispersed surfaceclusters of 37-mer is a remarkable achievement, especially, in light of fact that the largest monodispersed surface-clusters that has been reported to date contains merely 10 galliums 22 .…”

Strain-relief pattern as guide for the formation of surface-supported bimolecular nanoribbons

“…Examples of solid nanotemplates are the natural herringbone reconstruction of Au͑111͒, 6 its vicinal surfaces 7 and self-organized surface patterns occurring in heteroepitaxial systems, 8,9 which have been previously used to influence the formation of molecular as well as atomic assemblies. 4,7,[9][10][11][12][13][14][15][16][17] The triangular strain-relief pattern formed by 2 monolayers ͑ML͒ of Ag on Pt͑111͒ 8 is particularly interesting because the bare terraces of this template surface show a high affinity for the site selective molecular adsorption and for the guidance of homomolecular nanostructures. [14][15][16][17] In this letter, by investigating the case of a bimolecular system on Ag/Pt͑111͒, we demonstrate the possibility of controlling the formation of surface structure-guided heteromolecular nanoassemblies from properly designed molecular building blocks.…”

Fullerene on Nitrogen-Adsorbed Cu(001) Nanopatterned Surfaces: From Preferential Nucleation to Layer-by-Layer Growth

“…The nearest-neighbor lateral distances in all domains are in the range of 1.02 ( 0.04 nm, roughly 4 times that of the substrate Cu(001) lattice and close to an intermolecular distance of 1.002 nm in the close-packed plane of a C 60 fcc crystal. The same structure was widely observed in the growth of C 60 on various substrates, 6,8,20,30,33 where molecule-molecule interactions prevail over molecule-substrate interactions.…”

“…The use of surface cues to guide adsorption processes 13 has been demonstrated on a variety of spontaneously nanostructured substrates such as dislocation networks, 6 vicinal surfaces, 7 self-ordered biphase systems, 14,15 and so on. Molecular assembly on crystal surfaces is determined by a delicate balance between adsorbate-adsorbate and adsorbate-substrate interactions.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12] In particular, the controlled self-assembly of molecular nanostructures, both for fundamental research and future applications, remains a challenge. One of the methods to control self-assembly is the use of suitably designed functional groups in the molecular structure, which are able to participate in direct noncovalent interactions among the molecules.…”